This invention relates to a method for manufacturing a thin and flexible ribbon of dielectric material having desired electrical, mechanical and physical properties by melting dielectric material selected from the group consisting of LiNbO.sub.3, LiTaO.sub.3, NaTaO.sub.3, AgNbO.sub.3, WO.sub.3, NaNO.sub.2, BaTiO.sub.3, PbTiO.sub.3, Pb(Zr,Ti)O.sub.3, SrTiO.sub.2, Pb(Zn.sub.1/3 NB.sub.2/3)O.sub.3, Ba.sub.2 Nb.sub.2 O.sub.7, Ca.sub.2 Nb.sub.2 O.sub.7, Bi.sub.4 Ti.sub.3 O.sub.12, K.sub.x WO.sub.3 (0.43.ltoreq.x.ltoreq.0.51), PbNb.sub.2 O.sub.6 and their composites to form a one phase melt thereof; ejecting the melt against a moving surface of a cooling substrate; and cooling instantaneously and very rapidly the melt on the cooling surface.
Hitherto, various kinds of dielectric glasses have been known as dielectric material which can form an amorphous structure by cooling a melt thereof. For instance, dielectric glass sheets or plates can be obtained by taking up the melt of dielectric glass material between a pair of rolls. Further, a dielectric glass fiber can also be obtained by blowing the melt out of a nozzle. However, dielectric constants of dielectric glasses, such as Bi.sub.2 O, CdO and SiO.sub.2 are relatively small and usually lie within the range of 16-32. Any dielectric glass having a higher dielectric constant has not been found. Further, the dielectric glasses have the poor mechanical property, i.e., their impact resistance and heat resistance are poor and it is very difficult to work the dielectric glasses.
The dielectric materials described in the preamble are known to have relatively higher dielectric constants than the dielectric glasses. These dielectric materials form a crystalline structure in a solid state and thus are called as crystalline dielectric material in this specification. It is known to form a thin dielectric film or layer on a substrate by vapor-depositing, electric-depositing or sputtering these crystalline dielectric materials. The film thus formed includes partially the amorphous structure. However, by such known methods, it is impossible to produce a thin and flexible ribbon of dielectric material without using the substrate. In other words, the known methods could not form the thin ribbon of dielectric material which does not adhere to the substrate.
It is possible to obtain a thin plate or chip of dielectric material by slicing a rod of dielectric material. However, since the rod has wholly the crystalline structure, the obtained thin plate is also wholly of crystalline. Such a thin plate is quite fragile and thus could not be practically used in manufacturing devices and elements. Further, the dielectric constant of the thin plate is rather low. Moreover, the slicing is a quite cumbersome operation and thus it is impossible to form the thin plates at a high speed on a mass production.